In the field of digital image processing, scaling of an image is equivalent to the “zoom in” or “zoom out” at the time of a camera taking photos of a scene, where image amplification equals to “zoom in” and image reduction equals to “zoom out”. The degree of zooming of objects relates to the relative positions of the objects during the formation of the image.
However, in conventional art, when scaling an image using an image scaling algorithm, a same scaling ratio will be used for scaling the image. It does not take into account the relative positions of the objects during the formation of the image. Accordingly; the scaled image thus obtained is a planar image and does not accord with the depth relations in the scene.